for Journals by Title or ISSN
for Articles by Keywords
help
  Subjects -> ENGINEERING (Total: 2254 journals)
    - CHEMICAL ENGINEERING (190 journals)
    - CIVIL ENGINEERING (177 journals)
    - ELECTRICAL ENGINEERING (99 journals)
    - ENGINEERING (1198 journals)
    - ENGINEERING MECHANICS AND MATERIALS (386 journals)
    - HYDRAULIC ENGINEERING (55 journals)
    - INDUSTRIAL ENGINEERING (60 journals)
    - MECHANICAL ENGINEERING (89 journals)

ENGINEERING (1198 journals)

The end of the list has been reached or no journals were found for your choice.
Journal Cover Reactive and Functional Polymers
  [SJR: 0.879]   [H-I: 62]   [5 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1381-5148
   Published by Elsevier Homepage  [2969 journals]
  • Scalable synthesis of multicolour conjugated polymer nanoparticles via
           Suzuki-Miyaura polymerisation in a miniemulsion and application in
           bioimaging
    • Abstract: Publication date: Available online 30 August 2016
      Source:Reactive and Functional Polymers
      Author(s): Jonathan M. Behrendt, Jair A. Esquivel Guzman, Laura Purdie, Helen Willcock, John J. Morrison, Andrew B. Foster, Rachel K. O'Reilly, Mark C. McCairn, Michael L. Turner
      Suzuki cross-coupling polymerisation of aryldibromides and aryldiboronate esters in a sodium dodecyl sulfate (SDS)-stabilised miniemulsion provides a versatile and direct route to fluorescent conjugated polymer nanoparticles (CPNs). These nanoparticles have a conjugated backbone based on poly(9,9-dioctylfluorene) (PFO), however, significant structural diversity is introduced by incorporation of electron withdrawing, heterocyclic comonomers (5–50mol.%) in order to tune the emission wavelengths from blue to far-red/near-infrared. The robust nature of the polymerisation methodology allows for rapid assessment of the relationship between polymer composition, chain morphology and optical properties of the resultant CPNs. Moreover, the CPNs (after a simple and rapid purification step) can be used directly in fluorescence-based intracellular labelling experiments (in HCT116 cells), in which they display low cytotoxicity at biologically-useful concentrations.


      PubDate: 2016-08-30T17:03:38Z
       
  • Surface modification of poly(ethylene-butyl acrylate) copolymers by
           microwave methodology and functionalization with
           4-dimethylamino-N-(2-hydroxyethyl)-1,8-naphthalimide for acidity sensing
    • Abstract: Publication date: Available online 30 August 2016
      Source:Reactive and Functional Polymers
      Author(s): S. Fernández-Alonso, T. Corrales, J.L. Pablos, F. Catalina
      A new procedure was developed for functionalization in the solid phase by using microwave irradiation. Heterogeneous chemical modification of poly(ethylene-butyl acrylate) copolymer (EBA), hydrolysis, chlorination, and Schotten–Baumann reactions were monitored by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. EBA was superficially functionalized by a previously synthesized fluorescent dye, 4-dimethylamino-N-(2-hydroxyethyl)-1,8-naphthalimide, and the depth profile of the functionalized polymer was determined by confocal Raman spectroscopy. The new functionalized materials were also evaluated as an acidic pH sensor by determining the change in the spectroscopic properties of absorption and fluorescence with pH of the solution and vapor phases. To improve the wettability of the EBA surface, oxygen plasma treatment was used and the response time of the solid sensor was analyzed.


      PubDate: 2016-08-30T17:03:38Z
       
  • Molecular imprinting of 5-fluorouracil in particles with surface RAFT
           grafted functional brushes
    • Abstract: Publication date: Available online 28 August 2016
      Source:Reactive and Functional Polymers
      Author(s): D. Oliveira, C.P. Gomes, R.C.S. Dias, M.R.P.F.N. Costa
      Molecularly imprinted particles with surface grafted functional polymer brushes were synthesized and evaluated aiming at the targeting of 5-fluorouracil (5-FU). A molecular imprinting material for 5-FU was prepared through precipitation crosslinking polymerization, in the presence of a RAFT agent, and choosing either methacrylic acid (MAA) or 2-hydroxyethyl methacrylate (HEMA) as functional monomers. In a later step, different kinds of functional polymer brushes, namely poly(methacrylic acid), poly(2-hydroxyethyl methacrylate) and poly(N-isopropylacrylamide) were grafted in the particles through a “grafting from” process starting on the RAFT groups present in their surface. The accomplishment of 5-FU imprinting was proven through comparative drug uptake measurements with imprinted/non-imprinted materials. Enhancement of 5-FU release in alkaline conditions comparatively to acidic environments was shown for particles with different combinations of molecular imprinting and grafted functional brushes. The MAA imprinting system with PMAA grafted functional brushes shows the highest improvement in 5-FU release triggered by a pH change from 2 to 10. Furthermore, for particles with PNIPA grafted brushes, a boost in drug release was also shown at T =20°C as compared to 40°C. The novel achievements reported here put into evidence the combined benefits of molecularly imprinted particles with surface grafted functional polymer brushes concerning molecular recognition and stimulated 5-FU release.


      PubDate: 2016-08-30T17:03:38Z
       
  • Editorial Board
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106




      PubDate: 2016-08-20T16:53:27Z
       
  • Preparation of pH-sensitive micelles from miktoarm star block copolymers
           by ATRP and their application as drug nanocarriers
    • Abstract: Publication date: Available online 18 August 2016
      Source:Reactive and Functional Polymers
      Author(s): Lu-mei Huang, Li-dong Li, Le Shang, Qing-han Zhou, Juan Lin
      In this study, novel pH-sensitive micelles were prepared from miktoarm star block copolymer, mPEG-b-P(MMA-co-MAA)2, by the atom transfer radical polymerization (ATRP) technique and dialysis method. Molecular structures and characteristics of the micelles were confirmed by 1H nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), dynamic light scattering (DLS), and transmission electron microscopy (TEM). The self-assembled micelles have a very low critical micelle concentration, indicating a high colloidal stability in aqueous solution. Methotrexate (MTX) was selected as the model drug of poor solubility. A relatively high drug loading capacity was found, and the in vitro release studies revealed that about 26% of the drug was released in simulated gastric fluid (SGF, pH1.2) over 48h compared to the maximum drug release of about 98% in simulated intestinal fluid (SIF, pH7.4). Thus, the pH-sensitive micelles might serve as promising carriers for oral drug delivery of hydrophobic drugs with controlled release behavior.


      PubDate: 2016-08-20T16:53:27Z
       
  • Synthesis of block copolymer with photo-decomposable polyurethane and its
           photo-initiated domino decomposition
    • Abstract: Publication date: Available online 16 August 2016
      Source:Reactive and Functional Polymers
      Author(s): Yoshihito Ishida, Yukie Takeda, Atsushi Kameyama
      A block copolymer consisting of a photo-decomposable polyurethane and poly(methyl methacrylate) (PMMA) was developed. The end-functionalized polyurethane (P2) was synthesized by polycondensation with the end-functionalization reagents. P2 possesses the photosensitive o-nitrobenzyl group and the 2-bromoisobutyryl group as the initiator of the atom transfer radical polymerization (ATRP). The block copolymer (P2-b-PMMA) was synthesized by the ATRP of methyl methacrylate (MMA) with P2 as the macroinitiator. The P2 block in P2-b-PMMA was decomposed by photo-irradiation at 365nm by the initiation of the photo-fries rearrangement of the urethane linkage and the subsequent domino reaction consistent with the elimination of the aza-quinone methide and decarboxylation. The photo-initiated decomposition of the P2 segment in the thin-film state was accomplished.


      PubDate: 2016-08-20T16:53:27Z
       
  • Synthesis and Metal Complexation of Dual-functionalized Silsesquioxane
           Nanoparticles by Sequential Thiol–Epoxy Click and Esterification
           Reactions
    • Abstract: Publication date: Available online 5 August 2016
      Source:Reactive and Functional Polymers
      Author(s): Shun Shibasaki, Yusuke Sasaki, Kazuhiro Nakabayashi, Hideharu Mori
      Here, we demonstrate a convenient and robust method for fabricating a series of dual-functionalized silsesquioxane nanoparticles (SQ-NPs) using a thiol–epoxy click reaction and subsequent esterification. Epoxy-functionalized SQ-NP was initially prepared from commercially available (3-glycidyloxypropyl)triethoxysilane. A thiol compound, 2-mercaptopyridine, was used in the thiol–epoxy click reaction, and sulfur-containing acid chloride derivatives were used for subsequent functionalization via esterification. The resulting SQ-NPs have two chemically different groups on a single arm, which affords a high density of peripheral functional groups. The dual-functionalized SQ-NPs with the pyridine and thioether units led to the complexation with copper species, affording a stable Cu complex. This convenient synthetic approach provided dual-functionalized SQ-NPs with narrow size distributions (average particle diameter < 3 nm), reasonable molecular weights (M n = 3300–4200, M w/M n = 1.32–1.45), good solubility, relatively high refractive indices, and the ability to form characteristic metal complexes.


      PubDate: 2016-08-10T16:20:48Z
       
  • Non-isothermal DSC and rheological curing of ferrocene-functionalized,
           hydroxyl-terminated polybutadiene polyurethane
    • Abstract: Publication date: Available online 5 August 2016
      Source:Reactive and Functional Polymers
      Author(s): Beatriz Lucio and, José Luis de la Fuente
      The curing reaction of a novel linear segmented polyurethane (PU) based on a functional metallo-polyol derivative of hydroxyl-terminated polybutadiene (HTPB), (ferrocenylbutyl)dimethylsilane-grafted HTPB, and isophorone diisocyanate (IPDI) is studied under non-isothermal conditions. This reaction is of particular interest in advanced composite energetic materials for the aeronautic technology. Differential scanning calorimetry (DSC) indicates that the curing mechanism involves multiple reactions, which was further substantiated by a rheological analysis. Rheometry was used to analyse the chemorheological behaviour through the evolution of both complex viscosity (η ⁎ ) and storage modulus (Gʹ) at four different heating rates. The profiles obtained for the viscosity were applied to four- and six-parameter Arrhenius models. The curves of rheological conversion degree were also obtained from the elastic modulus data, and values for the activation energy of this polyaddition reaction were estimated by the application of Kissinger's method.


      PubDate: 2016-08-10T16:20:48Z
       
  • Synthesis, self-assembly and pH sensitivity of PDEAEMA–PEG–PDEAEMA
           triblock copolymer micelles for drug delivery
    • Abstract: Publication date: Available online 3 August 2016
      Source:Reactive and Functional Polymers
      Author(s): Guiyou Wang, Lingmei Zhang
      In this study, well-defined double-hydrophilic triblock copolymers, consisting of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(N,N-diethylamino-2-ethylmethacrylate) (PDEAEMA), were synthesized and characterized. The molecular weights of the copolymers were controllable. In the basic environments, the copolymers can self-assemble into the PDEAEMA core and PEG corona micelles in aqueous solution with an average size of 40–180nm. The low critical micelle concentration (CMC, about 10−3 mgmL−1) of copolymers investigated in pH7.4 aqueous solution confirmed the adequate thermodynamic stability of their self-assembly. As shown in the cytotoxicity assay, the copolymers have good biocompatibility. Doxorubicin (DOX) was encapsulated into the triblock copolymer micelles. The drug loading efficiency and entrapment efficiency values of DOX-loaded micelles reached 8.14% and 88.6%, respectively. The DOX release of the drug-loaded micelles depends on the pH values. These phenomena indicated that the double-hydrophilic PDEAEMA–PEG–PDEAEMA triblock copolymers have a potential application in the drug delivery.


      PubDate: 2016-08-05T16:07:34Z
       
  • Polyelectrolyte-catalyzed Diels–Alder reactions
    • Abstract: Publication date: Available online 30 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Nellepalli Pothanagandhi, Akella Sivaramakrishna, Kari Vijayakrishna
      Imidazolium-based poly(ionic liquids) bearing bromide and bis(trifluoromethane)sulfonimide as counteranions [poly(ViEIm)Br and poly(ViEIm)NTf 2 ] derived from reversible addition fragmentation chain transfer (RAFT) polymerization techniques are used in polymer-assisted solution phase Diels–Alder reactions between isoprene and a variety of dienophiles. With 5mol% loading, these polyelectrolytes exhibit very good catalytic activity toward Diels–Alder reaction with quantitative yields within 30min at room temperature. These polyelectrolyte-catalyzed reactions resulted in good para/meta-like product ratios. Here, the coordination nature of the positively charged imidazolium groups in polyelectrolyte with dienophiles plays a key role in catalyst activity and selectivity. These polyelectrolytes were reused for 4cycles without a significant loss in their catalytic activity and selectivity.
      Graphical abstract image

      PubDate: 2016-07-30T16:01:06Z
       
  • Modification of microbial polymers by thiol-ene click reaction:
           Nanoparticle formation and drug encapsulation
    • Abstract: Publication date: Available online 29 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Alberto Lanz-Landázuri, Antxon Martínez de Ilarduya, Montserrat García-Alvarez, Sebastián Muñoz-Guerra
      Comb-like amphiphilic polymers were obtained by grafting long paraffinic chains on microbial poly(γ,DL-glutamic acid) and poly(β,L-malic acid) through two steps, i.e. allylation of the carboxylic side groups followed by UV-initiated thiol-ene click reaction with 1-alkanethiols bearing 8, 12 and 16 carbon atoms, and their characterization was accomplished by 1H NMR, GPC and DSC. The grafted polymers were capable of self-assembling in nanoparticles with diameters in the 80–240nm range. Incubation in water under physiological conditions led to hydrolysis of the lateral ester bonds followed by scission of the polyamide or polyester main chain. The model drugs, Theophylline and Carbamazepine, were efficiently encapsulated in these systems with much better results attained for the later. Drug release from nanoparticles incubated under physiological conditions occurred with a burst effect and were completely discharged in 24h. Release profiles recorded from drug-loaded films suggested that the drug was delivered in both cases through a diffusion process.


      PubDate: 2016-07-30T16:01:06Z
       
  • Sequential separation method for the determination of uranium and thorium
           in soil using diamyl amylphosphonate and Aliquat®336 impregnated polymer
           resins
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106
      Author(s): Young Gun Ko, Jong-Myoung Lim, Hoon Lee, Kun Ho Chung, Mun Ja Kang
      The accurate and rapid determination of radionuclides in soil is very important to monitor the radioactivity of radionuclides for reduction of hazardous effects to human health. Here, a sequential separation method with a fusion technique was developed to separate uranium and thorium isotopes from a soil sample using polymer resins (UTEVA® and TEVA®) packed columns. The radioactivity of separated U and Th was measured using alpha-particle spectrometry. The developed method was evaluated by assessing the key validation parameters of the selectivity, radioactivity range of linearity, scores for quality control, accuracy, tracer recovery yield, and quantification of uncertainty. The method offered a fast analysis of U and Th isotopes of the soil samples with very high chemical recovery yield and the effective removal of interferences, and demonstrated a satisfactory quality level for the selected criteria of the performance for the method validation. The developed method might be promising for use in a determination of the radioactivity of solid samples containing various interferences.


      PubDate: 2016-07-26T15:54:07Z
       
  • A novel core@shell magnetic molecular imprinted nanoparticles for
           selective determination of folic acid in different food samples
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106
      Author(s): Sajjad Hussain, Sabir Khan, Saima Gul, Maria Isabel Pividori, Maria Del Pilar Taboada Sotomayor
      In this work, magnetic molecularly imprinted polymers (MMIPs) were synthesized and tested for the determination of folic acid (FA) in different food samples. The MMIPs were polymerized at the surface of Fe3O4@SiO2 magnetic nanoparticles (MNPs) using acrylonitrile (functional monomer), ethylene glycol dimethacrylate (EGDMA) as cross-linking agent and azobiisobutyronitrile (AIBN) as an radical initiator. The morphological, topological and chemical characteristics of the MMIPs were investigated by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared (FTIR) techniques. The physico-chemical characterization, such as adsorption capacities and selectivity of MMIPs was investigated and compared with the respective MNIPs. The adsorption experimental data demonstrate that maximum adsorption capacity of MMIP at equilibrium was 8mgg−1 and than the adsorption process of FA over MMIPs follows Freundlich adsorption isotherm model and pseudo-first-order reaction kinetic. For evaluation of this new proposed material, the recovery studies were carried out in spiked samples at different concentration levels and the obtained values were in the range of 95–104% for orange and for spinach the recoveries were between 99.5 and 102.5%. The relative standard deviations (RSD) for the recoveries were <0.5% for both samples. These results demonstrate that this novel MMIP material can be efficiently used for the selective extraction of folic acid from different food complex matrices.


      PubDate: 2016-07-26T15:54:07Z
       
  • Novel composites from green unsaturated polyesters and fly ashes:
           Preparation and characterization
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106
      Author(s): A.S.M. Trino, C.S.M.F. Costa, A.C. Fonseca, I. Barata, E. Júlio, A.C. Serra, J.F.J. Coelho
      New composites from unsaturated polyesters (UPs), with high ‘green’ content, and fly ashes (FA) were studied for the first time. All the monomers used in the synthesis (fumaric acid, succinic acid, propylene glycol, 1,3-propanediol) can be obtained from renewable resources, with the exception of diethylene glycol. The composites were prepared by crosslinking the UPs in the presence of FA, using styrene (St), methyl methacrylate (MMA) and a mixture of acrylated epoxidized soybean oil (AESO) with St as reactive solvents. The results showed that the incorporation of the FA improved the thermal stability of the composites. Regarding the thermomechanical properties, it was found that the incorporation of 50% (w/w) FA led to composites with higher elastic modulus (E′) and higher glass transition temperature (T g) than the neat polymeric matrix. These observations indicate a good compatibility between the FA and the polymeric matrix.


      PubDate: 2016-07-26T15:54:07Z
       
  • Controlling the polymer-nanolayer architecture on anion-exchange membrane
           adsorbers via surface-initiated atom transfer radical polymerization
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106
      Author(s): Jan Schwellenbach, Peter Kosiol, Björn Sölter, Florian Taft, Louis Villain, Jochen Strube
      The immobilization of a polymer-nanolayer containing ligand sites is a widely used approach to increase the binding capacity of membrane adsorbers. In this work strong anion-exchange membrane adsorbers were produced via surface-initiated atom transfer radical polymerization (SI-ATRP) using a monomer bearing a quaternary amine group (Q-type). Additionally the architecture of the polymer-nanolayer has been controlled with respect to the length and density of the grafted polymer chains and in terms of ligand density and interchain crosslinking degree. The influence of these architecture parameters on the membrane permeability and the static binding capacity towards bovine serum albumin (BSA) as a model protein has been investigated. It could be shown that these parameters have a major impact on the performance of the produced membrane adsorbers. While the chain-length and –density significantly increase the binding capacity, a decrease in permeability is observed. The interchain crosslinking degree and a reduction of the ligand density increase the permeability, but simultaneously the static binding capacity is slightly diminished. A well-chosen combination of these architecture parameters can produce membrane adsorbers with static binding capacities >100mg/mL membrane volume (MV) while still maintaining a specific permeability >40mL/(min·cm2·bar), far superior to commercially available products.


      PubDate: 2016-07-26T15:54:07Z
       
  • Synthesis and characterization of thermoset imidazolium bromide ionomers
    • Abstract: Publication date: Available online 26 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Monika R. Kleczek, Ralph A. Whitney, Andrew J. Daugulis, J. Scott Parent
      Elastomeric ionomers are prepared via halide displacement from brominated poly(isobutylene-co-isoprene) (BIIR) with various imidazole-based nucleophiles. Reaction of BIIR with imidazole or 1,1′(1,4-butanediyl)bis(imidazole) in a single-step, solvent-free elastomer compounding approach is used to synthesize thermoset derivatives, in addition to a two-step process involving reaction of BIIR with 1-vinylimidazole (VIm), followed by peroxide-initiated cross-linking. The physical properties of these ionomeric thermosets are the product of their covalent and ionic networks. Ion-pair aggregation contributes significantly to dynamic storage modulus and low-strain static tensile modulus, but extensive relaxation of this labile network minimizes its influence over timescales larger than 1min. The adhesive properties and antibacterial activity against E. coli provided by these ionomers are also demonstrated.


      PubDate: 2016-07-26T15:54:07Z
       
  • Graphene oxide–enriched double network hydrogel with tunable
           physico-mechanical properties and performance
    • Abstract: Publication date: Available online 25 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Sepideh Mohammadi, Hamid Keshvari, Mahnaz Eskandari, Shahab Faghihi
      An emerging approach to obtain polymeric hydrogels with superior properties is integrating carbon-based nanomaterials within their network structure. On the other hand, hydrogels with tailored physical and mechanical characteristics are desirable class of materials which have extensive application in drug delivery and tissue engineering. This study presents a strategy to achieve graphene oxide (GO)-enriched hydrogels with modulated physico-mechanical properties and performance. GO/poly acrylic acid (PAA)/gelatin hydrogels are fabricated via in situ polymerization method followed by chemical crosslinking of gelatin molecules. N,N′-Methylenebisacrylamide (BIS) in a various concentrations is used within the prepolymer composition as cross-linking agent to prepare a set of nanocomposite hydrogels. Fourier transform infrared (FTIR), X-ray diffraction (XRD), and atomic force microscopy (AFM) are utilized to characterize the fabricated hydrogel samples. The microstructure of samples is analyzed with scanning electron microscopy (SEM). The mechanical properties of the specimens are evaluated by rheometry. The swelling behavior, degradation kinetic and porosity of the hydrogels as well as their in vitro cytotoxicity are also assessed. The results show successful synthesis of nano GO sheets and polymer composites. The increase of cross-linker concentration is decreased the swelling ratio and increased the porosity of hydrogel samples. A wide range of pore diameters (70–300μm) and mechanical stiffness (storage modulus of 2000–25,000Pa) is obtained. Through manipulation of cross-linking density the degradation rate of nanocomposite hydrogels is controlled. Finally, no toxicity is detected by exposure of the hydrogel extracts to osteoblast osteosarcoma cells. The optimized hydrogel samples having appropriate range of physical characteristics and functionality suggest the application of the 3D structures as scaffold material for hard tissue construction.
      Graphical abstract image

      PubDate: 2016-07-26T15:54:07Z
       
  • Superb adsorption capacity and mechanism of
           poly(1-amino-5-chloroanthraquinone) nanofibrils for lead and trivalent
           chromium ions
    • Abstract: Publication date: Available online 25 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Shaojun Huang, Chengzhang Ma, Yaozu Liao, Chungang Min, Ping Du, Yanqin Zhu, Yubo Jiang
      Poly(1-amino-5-chloroanthraquinone) (PACA) nanofibrils were applied as new nano-adsorbents for heavy metal removal from aqueous solutions. Adsorption properties including adsorption capacity, selectivity, kinetics, mechanism, and isotherm of PACA nanofibrils were studied in detail. The competitive adsorption of the nanofibrils for Pb(II) and Cr(III) in binary mixture systems was investigated. The results showed that Pb(II) and Cr(III) were adsorbed preferentially over the other metal ions including Hg(II), Cr(VI), Zn(II), Cd(II), Fe(III) and Cu(II), under competitive conditions. Kinetic data indicated that the adsorption process of PACA nanofibrils for Pb(II) and Cr(III) achieved equilibrium within 2 h following a pseudo-second-order rate equation and exhibiting a three-stage intraparticle diffusion mode. The adsorption mechanism of PACA nanofibrils for Pb(II) and Cr(III) was investigated by Fourier transform infrared spectra (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses. The adsorption isotherms of Pb(II) and Cr(III) fitted well with the Langmuir model, exhibiting superb adsorption capacity of 4.27 and 4.22 mmol of metal per gram of adsorbent, respectively. Furthermore, adsorption–desorption experiments demonstrated that the PACA nano-adsorbents could be easily recycled without considerable changes in the adsorption capacity.


      PubDate: 2016-07-26T15:54:07Z
       
  • A novel gelatin-AgNPs coating preparing method for fabrication of
           antibacterial and no inflammation inducible coatings on PHBV
    • Abstract: Publication date: Available online 25 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Xingxing Zhao, Hairong Liu, Yibing Hu, Jiying Huang, Shuihan Zhang, Fei Ja
      Silver nanoparticles (AgNPs) based antibacterial materials are widely applied to commodity and clinic wound treatments. However, genotoxicity and inflammatory response induced by AgNPs inhibit their application as the antibacterial coating of medical devices like catheters. A novel gelatin-AgNPs coating manufacture method was introduced here to generate an antibacterial coating, which nearly immunes to inflammatory, on basal PHBV material. The novel gelatin-AgNPs coating was produced by immobilizing gelatin on the Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) membrane and subsequently fixing AgNPs on acquired gelatin coating. Prepared gelatin-AgNPs coatings displayed considerable antibacterial capacity. These gelatin-AgNPs coatings did not cause inflammation, growth inhibition or apoptosis to normal human embryonic lung fibroblasts, MRC-5 cells, by analyzing the transcription levels of relevant genes in these cells incubated with tested coatings for 4days. Hence, this novel gelatin-AgNPs coating manufacture method paved its way to apply in medical devices manufacture including catheters.


      PubDate: 2016-07-26T15:54:07Z
       
  • Epoxy-thiol thermosets modified by carbazole decorated hyperbranched
           poly(ethyleneimine) for optical applications
    • Abstract: Publication date: Available online 25 July 2016
      Source:Reactive and Functional Polymers
      Author(s): O. Korychenska, C. Acebo, M. Bezuglyi, A. Serra, V.J. Grazulevicius
      New epoxy-thiol thermosets containing carbazolyl moieties were prepared by adding different proportions of a hyperbranched poly(ethyleneimine) with carbazolyl terminated units to diglycidylether of bisphenol A/trimethylolpropane tris(3-mercaptopropionate) stoichiometric formulations. This carbazolyl decorated hyperbranched polymer was synthesized from commercially available hyperbranched poly(ethyleneimine) and N-glycidyl carbazole and was characterized by standard procedures. The influence of adding different proportions of the modifier to the formulation on the curing process was determined by calorimetry after the selection of the most adequate latent initiator, which was a urethane compound, named PDU-250. Its decomposition at a well-defined temperature liberates the amine that initiates the thiol-epoxy curing process. The materials obtained with different proportions of modifier were characterized by means of thermomechanical analysis. On increasing the proportion of modifier, the glass transition temperature and the damping characteristics increased, but the thermal stability and the homogeneity were reduced. The films obtained by curing the different formulations exhibited fluorescence maxima at 370–374nm. The fluorescence quantum yields were in the range of 17–32% and they decreased with the increase of the amount of the modifier in the materials.
      Graphical abstract image

      PubDate: 2016-07-26T15:54:07Z
       
  • RAFT polymerization and dually responsive behaviors of
           terpyridine-containing PNIPAAm copolymers in dilute solutions
    • Abstract: Publication date: Available online 22 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Hongwei Zhou, Fengshou Liang, Jie Li, Xiaobin Ding, Aijie Ma, Weixing Chen, Chunyan Luo, Gai Zhang, Wei Tian, Ming Cheng, Benchuan Liao
      Introduction of new components is an effective way to gain new functionalities and to regulate the properties of responsive polymers. In the present work, a RAFT polymerization approach to terpyridine-containing poly(N-isopropyl acrylamide) (PNIPAAm) copolymers was developed and the dually responsive behavior of the obtained polymer to temperature variation and metal ions in dilute solutions were investigated. By utilizing RAFT polymerization, the molecular weight polydispersity index of the polymer can be reduced compared with the traditional free radical polymerization method. Due to the coexistence of thermosensitive component and terpyridine, the synthesized polymer is thermosensitive and metal ion sensitive. Further titration investigation revealed that this polymer may be utilized as a water-soluble and colorimetric sensor for Fe2+ and Fe3+ and the obvious color change from a colorless state to a purple state makes the polymer a potential sensor to detect Fe2+ and Fe3+ macroscopically by naked eye. Overall, the terpyridine-containing poly(N-isopropyl acrylamide) copolymers may enrich the family of terpyridine-containing polymers and provide some clues for developing new multi-responsive and multi-functional polymers.


      PubDate: 2016-07-26T15:54:07Z
       
  • Development of high dielectric polyimides containing bipyridine units for
           polymer film capacitor
    • Abstract: Publication date: Available online 22 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Xinwen Peng, Wenhui Xu, Linlin Chen, Yichun Ding, Tianrou Xiong, Shuiliang Chen, Haoqing Hou
      Polymer dielectrics with high dielectric constant, low dielectric loss, high breakdown strength, and high temperature capability are attractive for applications such as capacitive energy-storage. Commercially available polymer dielectrics such as biaxially oriented polypropylene (BOPP), poly(ethylene terephthalate) (PET), poly(ethylene naphthalate) (PEN), polycarbonate (PC), and poly(vinylidene) fluoride (PVDF) can be just operated below 200°C. Great effort has been put into exploring high temperature polymer dielectrics to fulfill the demand of high temperature applications, such as the aerospace and military power supply. In this study, a series of polyimides containing bipyridine units with good dielectric performance and high temperature capability were prepared by using a newly synthesized diamine monomer, (5,5′-bis [(4-amino) phenoxy]-2,2′-bipyridine (BPBPA)). These polyimides possessed high dielectric constant of the as-synthesized polyimides can be up to7.2, the dielectric loss was <0.04, and the energy density was up to 2.77J/cm3. Furthermore, the polyimides exhibited high glass transition temperature (Tg) of 275–320°C and tensile strengths of 175–221MPa. These obtained polyimides promise potential applications in high temperature flexible polymer film capacitor operated at high temperature.


      PubDate: 2016-07-26T15:54:07Z
       
  • Facile tunning the morphology and porosity of a superwetting conjugated
           microporous polymers
    • Abstract: Publication date: Available online 22 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Peng Mu, Hanxue Sun, Jiake Zang, Zhaoqi Zhu, Weidong Liang, Fucheng Yu, Lihua Chen, An Li
      A series of conjugated microporous polymers (CMPs) were synthesized via palladium-catalyzed Sonogashira-Hagihara crosscoupling polycondensation of N,N-bis(4-bromobenzyl)amine and 1,3,5-triethynylbenzene in different ternary solvents. The globular, tubular and amorphous CMP networks with different BET (Brunauer-Emmett-Teller) surface areas were obtained. Take advantages of superhydrophobic/oleophilic properties and micoporous morphological structures of the resulting CMPs, a CMPs-based mesh film and a flexible, superhydrophobic, transparent CMPs-based film were prepared, which exhibit good oil/water separation performance and moderate transmittance. In addition, due to its abundant porous feature and unique chemistry nature of the as-prepared N-containing CMPs, the removal of the dyes from water and iodine from organic solvent have been investigated. The results show that the CMP-3 possesses the highest adsorption capacities of 269mgg−1 for rhodamine B, 198mgg−1 for methyl orange and 218mgg−1 for iodine, respectively. This work provides a useful guidance for design and construction of porous CMPs materials for special applications.


      PubDate: 2016-07-26T15:54:07Z
       
  • Design, synthesis, characterization and magnetic studies of the
           metal-quinolate PHEMA-b-HQ polymer micelles
    • Abstract: Publication date: Available online 22 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Rong Ren, Yanhua Wang, Weilin Sun
      Metal coordinated micelles based on the diblock copolymer PHEMA82-b-HQ78 were synthesized. The block PHQ with 8-hydroxyquinoline groups can coordinate with metal ions to form the crosslinked core for micellization, while the other block PHEMA in the shell of the micelle improves its solubility. The morphological characteristics and the coordinating interaction between the metal ions and the core segment were characterized by DLS and TEM. The magnetic measurement found that the Curie-Weiss temperature T θ of the metalized micelle was 56K and its hysteresis loop exhibited the typical ‘S′ shape with low H c and M r. at 5K, indicating that this micelle had the properties of soft ferromagnetic materials.


      PubDate: 2016-07-26T15:54:07Z
       
  • Synthesis, morphology investigation and thermal mechanical properties of
           dopamine-functionalized multi-walled carbon nanotube/poly(amide-imide)
           composites
    • Abstract: Publication date: Available online 22 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Shadpour Mallakpour, Amin Zadehnazari
      Here, poly(amide-imide) (PAI) composites containing multi-walled carbon nanotubes (MWCNT) were synthesized with solution casting method. To improve the dispersion and compatibility with the polymer matrix the MWCNT was surface-modified with dopamine biomolecule under microwave irradiation. The prepared dopamine-functionalized MWCNT (MWCNT-Dop) was characterized for their structure, morphology, and thermal behavior employing Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis, field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The results consistently confirmed the formation of dopamine functionalities on MWCNT. The MWCNT-Dop/PAI hybrid films were also characterized extensively using FT-IR and XRD techniques. The microstructure of the composites was studied by FE-SEM and TEM, in terms of the dispersion state of the nanotubes and the polymer-nanotube interface. The thermal behavior and mechanical properties of the resultant composites were also studied. In comparison with neat PAI, the MWCNT-Dop reinforced composites posses higher thermal stability, tensile strength and Young's modulus.


      PubDate: 2016-07-26T15:54:07Z
       
  • The synthesis and absorption dynamics of a lignin-based hydrogel for
           remediation of cationic dye-contaminated effluent
    • Abstract: Publication date: Available online 22 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Chenghua Yu, Feng Wang, Chunhui Zhang, Shiyu Fu, Lucian A. Lucia
      Lignosulfonate-g-acrylic acid (LS-g-AA) hydrogels that possess superabsorbent capacity were synthesized by grafting acrylic acid (AA) on the backbone of lignosulfonate (LS) in the presence of N,N′-methylene-bis-acrylamide (MBA) as initiated by laccase/t-BHP(tert-butyl hydroperoxide). Specifically, the carboxylic acid groups introduced by grafting acrylic acid, significantly enhanced the absorption capacity of LS-g-AA hydrogels. In this case, methylene blue (MB) was the representative dye substrate to study absorption dynamics. It was found that the equilibrium absorption of MB reached 2013mg•g−1 while pH, absorption time, and initial MB concentration affected the overall absorption capacity. The absorption isotherms and kinetics obeyed standard Freundlich and pseudo-2nd-order models, respectively. Furthermore, preliminary desorption experiments were conducted in weak acid solution and showed that ~50% of the original MB could be removed over one rinse cycle.


      PubDate: 2016-07-26T15:54:07Z
       
  • Synthesis and characterization of imidacloprid microspheres for controlled
           drug release study
    • Abstract: Publication date: Available online 20 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Qiaohong Zheng, Hongchun Li, Yongsheng Niu
      Polypropylene carbonate (PPC) was synthesized by the alternating copolymerization of carbon dioxide with propylene oxide (PO). Imidacloprid microspheres were prepared by emulsion solvent evaporation, PPC as the drug-carrier material. The effect of the reaction conditions on drug loading (DL) and entrapment efficiency (EE) was examined. High DL of 45.03% was achieved at the methylene chloride and water volume ratio of 1:1, polyvinyl alcohol (PVA)-1788 concentration of 1%, imidacloprid and PPC mass ratio of 1:3, and shear rate of 10,000r/min. When imidacloprid and PPC mass ratio was 2:3, high EE of 77.91% was obtained. Through the scanning electronic microscopy (SEM) the hollow structure of the microspheres was studied. The effects of shear rate on the diameter and morphology of microspheres were studied by the SEM. The perfect microspheres were obtained at the 10,000r/min shear rate. The release behavior of imidacloprid encapsulated in the microspheres was studied. The experimental results indicated that the microspheres had a property of sustained drug release.


      PubDate: 2016-07-26T15:54:07Z
       
  • Thiol-ene-clickable and emissive carbazole-based polymer networks with
           tunable colors
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106
      Author(s): Ceylan Doyranli, Sümeyra Büyükçelebi, Sermet Koyuncu, Özlem Usluer, Mahmut Kus, Fatma Baycan Koyuncu
      Band gap tuning and processability of organic materials are significant topics for both scientific research and commercial applications. In this study, we synthesized a series of main chain cross-linkable polymers by thiol-ene click chemistry from N-allyl carbazole and different heterocycles via conventional Suzuki coupling polymerization reaction. The emission color of polymers could be successfully tuned from blue to red by attaching different benzazole-acceptor moieties to the carbazole donor unit. We also investigated the effects of cross-linking with respect to the amount of pentaerythritol tetrakis(3-mercaptopropionate) cross-linker on the optical, electrochemical, and surface morphological properties of the polymer films. The results showed that these polymers can be used as emissive active layers in solution-processable multilayer organic light-emitting diodes.


      PubDate: 2016-07-19T15:02:51Z
       
  • Editorial Board
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105




      PubDate: 2016-07-19T15:02:51Z
       
  • Development of Crystal Violet encapsulation in pectin - Arabic gum gel
           microspheres
    • Abstract: Publication date: Available online 11 July 2016
      Source:Reactive and Functional Polymers
      Author(s): Mariana V. Revuelta, M. Elizabeth Chacon Villalba, Alba S. Navarro, Jorge A. Güida, Guillermo R. Castro
      Six pectins with 35% to 91% methoxylation degree were purified and characterized to encapsulate Crystal Violet (CV). Amidated low methoxylated pectin (ALMP) was selected based on microsphere morphologies, aqueous solubility, viscosity and the effect of calcium concentration. Pectin microspheres were stabilized with Arabic gum (AG) and optimized according to the loading. Microspheres composed of 2.0% ALMP-1.0% AG crosslinked with 450mM calcium(II) were able to encapsulate 217±2μM CV. Optical microscopy of the gels revealed spheroid microspheres with 250±50μm diameter containing homogenous CV distribution. Dried microspheres observed by SEM and epifluorescence showed a highly shrinkable matrix keeping the spheroidal morphology. Low relative viscosity of the ALMP-AG-CV solutions was found compared to ALMP and ALMP-AG. The Young moduli (60–80Pa) of ALMP-AG microspheres by texturometric analysis indicated that the CV could interfere with the gel crosslinking. Raman spectroscopy analysis suggested some interaction of CV nucleophilic center within the matrix. FTIR of the matrix showed largest shifts in the carbonyl and carboxylate groups probably associated to H-bridges. CV stability studies performed on ALMP-AG microspheres, synthetized from polymer solutions with pH values above and below pectin pKa and showed faster CV release rates in presence of ionic strength.


      PubDate: 2016-07-14T14:20:35Z
       
  • Methylene blue removal by alginate–clay quasi-cryogel beads
    • Abstract: Publication date: September 2016
      Source:Reactive and Functional Polymers, Volume 106
      Author(s): Güler Uyar, Hakan Kaygusuz, F. Bedia Erim
      Nowadays, dyes constitute a large part of pollutants and have long been used in dyeing, paper and pulp, textiles, plastics, leather, cosmetics, and food industries. Among the conventional dye removal techniques, adsorption is prominent. Research challenges are on developing low-cost, biodegradable and efficient adsorbents. This study investigates polysaccharide–clay composite beads for the removal of methylene blue dye. Alginate–montmorillonite composite beads were prepared and then a novel cryogelation-like strategy was developed by deep-freezing the alginate beads at −21°C. This process changed the morphology of beads and improved surface area and adsorption capacity. The results of the batch adsorption experiments were modeled using isothermal, kinetic, and thermodynamic models. It is found that the adsorption is favorable and follows physical mechanism, with an endothermic process up to 40°C. The prepared composite beads are candidates for effective adsorbents for the dye removal.


      PubDate: 2016-07-09T13:14:32Z
       
  • Bio-based high performance epoxy-anhydride thermosets for structural
           composites: The effect of composition variables
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Adlina Paramarta, Dean C. Webster
      The structure-property relationships of a designed series of anhydride-cured epoxidized sucrose soyate (ESS) thermosets were studied. Epoxidized sucrose soyate is a novel bio-based epoxy resin derived from sucrose and soybean oil fatty acids, and it contains an average of 12 epoxy functional groups per molecule. This epoxy resin was crosslinked with methyl hexahydrophthalic anhydride to form polyester thermosets with high crosslink density, and a zinc-complex catalyst was used. In this study, the impact of composition variables—anhydride-to-epoxy molar ratio and catalyst amount—on the chemical, mechanical, and thermal properties of the thermosets was examined. All of the thermoset samples had very high gel fraction, which indicated excellent network connectivity. Samples made using an equimolar ratio of anhydride-to-epoxy groups had lower conversion of functional groups as shown by the somewhat lower gel fraction and higher moisture absorption. Analysis of the thermomechanical and tensile properties of the thermosets suggests that there is a factor interaction between anhydride-to-epoxy molar ratio and catalyst amount. Furthermore, the results suggest that the molecular networks of the thermoset samples are fairly complex due to the simultaneous competing reactions between catalyst-initiated epoxy-anhydride, hydroxyl-initiated epoxy-anhydride, and epoxy homopolymerization.


      PubDate: 2016-07-09T13:14:32Z
       
  • Structure of hydrogen bonded supramolecular self-assembles controlled by
           the structure of monomers: 1,1- and 1,3-diethylureas
    • Abstract: Publication date: Available online 7 June 2016
      Source:Reactive and Functional Polymers
      Author(s): Jolanta Świergiel, Jan Jadżyn
      Asymmetrically disubstituted 1,1-diethylurea, the moiety HNH·CO of which is capable of forming intermolecular hydrogen bonds with the possibility of creating two extremely different supramolecular entities: i) highly polar polymeric chains, analogous to those created by secondary amides, and ii) non-polar cyclic dimers, analogous to those created by lactams, in the experiment reveals exclusively the cyclic dimers. A solution of 1,1-diethylurea in non-polar solvent (with the mole fraction of urea 0.04) exhibits very low permittivity (about 3) what is in marked contrast to the permittivity (about 11) of analogous solution of symmetrically disubstituted 1,3-diethylurea, known for its strong chain polymerization.The difference of two orders of magnitude in the electrical conductivities of 1,1- and 1,3-diethylurea (ionically undoped) solutions suggests a probable participation in the conductivity of the protons released in process of thermal rupture of the hydrogen bonds linking 1,3-diethylurea molecules in supramolecular polymeric chains.


      PubDate: 2016-06-15T13:31:59Z
       
  • Linear amphiphilic TEMPO-grafted poly(ether sulfone) as polymeric
           interfacial catalyst: Synthesis, self-assembly behavior, and application
    • Abstract: Publication date: Available online 15 June 2016
      Source:Reactive and Functional Polymers
      Author(s): Liang Chen, Jun Tang, Qi Zhang, Jianli Wang
      In this study, we report the development of a novel recyclable polymer-supported interfacial catalyst for Montanari oxidation. The catalyst was prepared by immobilization of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) on poly(ether sulfone) (PES) bridged by imidazole groups and characterized by 1H nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, elemental analysis, contact angle measurement, and transmission electron microscopy (TEM). This well-designed polymer was self-assembled into nanoaggregates in CH2Cl2. It was then used as Pickering emulsifier in Montanari oxidation system (NaClO/NaBr/immobilized TEMPO) for selective oxidation of different alcohols, which exhibited higher activity due to the enhanced mass transfer through microreactor mechanism. Moreover, this polymeric interfacial catalyst was pH-sensitive and could be easily recycled by adding small amount of acid, and subsequent cycles of alcohol oxidation showed no loss on either conversion or selectivity. This study represents an innovative approach for developing polymeric interfacial catalyst.
      Graphical abstract image

      PubDate: 2016-06-15T13:31:59Z
       
  • Editorial Board
    • Abstract: Publication date: July 2016
      Source:Reactive and Functional Polymers, Volume 104




      PubDate: 2016-06-15T13:31:59Z
       
  • Deposition of Au nanoshells on thermally grown patterned Ag nanoparticles
           from the block copolymer micelle thin films by seeding method
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Himadri Acharya
      A facile method of fabricating patterned Ag–Au core–shell nanoparticles has been demonstrated using stepwise reduction and seeded deposition from block copolymer (BCP) micelle thin films. Spherical inverse micelles of polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP) copolymer in PS-selective toluene produce organic–inorganic complexes by coordinating silver acetate salt (Ag salt) to the hydrophilic P4VP core. Rapid thermal decomposition of Ag salt-loaded BCP micelles at 300°C for 5min leads to the formation of stable Ag nanoparticles of 20–25-nm size on a quartz substrate. The variations in annealing temperature, time, and substrate types influence the resulting Ag nanostructures. Transmission electron microscopy investigations reveal that gold (Au) shells of approximately 2.5-nm size on the Ag nanoparticles have been deposited by the seeding method using a selective reducing agent. Ag–Au core–shell nanoparticles can also help to control the hybridized surface plasmon band.


      PubDate: 2016-06-15T13:31:59Z
       
  • Adsorption and release studies of cefuroxime sodium from acrylic ion
           exchange resin microparticles coated with gellan
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): S. Racovita, M.A. Lungan, I. Bunia, M. Popa, S. Vasiliu
      Two types of microparticles based on acrylic ion exchange resin were prepared and used as macromolecular supports for the adsorption of an antibiotic (cefuroxime sodium salt) from aqueous solution. The first type of microparticles was synthesized by aqueous suspension copolymerization of acrylonitrile, ethylacrylate and ethylene glycol dimethacrylate followed by the aminolysis reaction of ternary copolymer with hydrazine hydrate. For the preparation of the second type of microparticles the gellan was selected to cover the surface of acrylic ion exchanger in order to increase the biocompatibility of these systems. Batch adsorption studies regarding the effects of various parameters such as, temperature, contact time, initial concentration of drug, drug:microparticles ratio and pH were studied. To study the adsorption kinetic mechanism, the Lagergren, Ho, Elovich and Weber-Morris particle diffusion models were applied and it was found that the adsorption of the drug could be described by pseudo first order equation (Lagergren model). The calculated values of thermodynamic parameters (ΔG, ΔH, ΔS) showed that the adsorption process was spontaneous and endothermic. The drug release process was found to be controlled by diffusion of drug molecules through polymer networks.


      PubDate: 2016-06-15T13:31:59Z
       
  • Energy-level tuning of poly(p-phenylenebutadiynylene) derivatives by click
           chemistry-type postfunctionalization of side-chain alkynes
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Dong Wang, Ruirui Zhang, Hong Gao, Xiangke Wang, Huihui Wang, Zhou Yang, Wanli He, Hui Cao, Jianming Gu, Huiying Hu, Huai Yang
      A series of poly(p-phenylenebutadiynylene) polymers substituted with electron-rich alkynes as the side chain were synthesized by homocoupling polymerization of asymmetric bifunctional monomers. The electron-rich alkynes underwent “click chemistry” with tetracyanoethylene (TCNE) to produce donor–acceptor chromophores. Optical and electrochemical characterizations clearly indicated that the energy level and band gap of P2 could be precisely controlled by the addition of acceptor molecules. One of the most important conclusions of this study is that a linear relationship between the lowest occupied molecular orbital (LOMO) and the amount of TCNE was observed. From the Z-scan measurement, all the compounds exhibited very special nonlinear optical properties, which suggested a tendency to transfer from saturable absorption (SA) to reverse saturable absorption (RSA).


      PubDate: 2016-06-15T13:31:59Z
       
  • Ultrafast and efficient removal of cationic dyes using a magnetic
           nanocomposite based on functionalized cross-linked poly(methylacrylate)
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Ali Pourjavadi, Azardokht Abedin-Moghanaki
      In this study, a new magnetic nanocomposite was synthesized via radical polymerization of methyl acrylate onto modified magnetic nanoparticles followed by the functionalization of the methyl ester groups with ethylenediamine and sodium chloroacetate. The generated magnetic nanocomposite was characterized by FT-IR, TEM, SEM, TGA, VSM, XRD and elemental analysis. Its key role as an adsorbent for the removal of typical cationic dyes, methyl violet and malachite green was investigated in terms of pH, contact time and initial dye concentration. The resulted adsorbent displays excellent adsorption capacities for cationic dyes which are more effective than most of the adsorbents reported so far. Study of the kinetic and isotherm of adsorption indicated that dyes adsorption process is well-described by pseudo-second-order-kinetic and Langmuir isotherm models, respectively. Furthermore, to find an accurate correlation between the adsorption enthalpy (ΔH) and experimental maximum adsorption capacity (qm), calculation of the adsorption enthalpy of a series of cationic dyes onto MNC-EDDA adsorbent was investigated using density functional theory (DFT). Interestingly, an excellent agreement between experimental qm and calculated ΔH (kcal/mol) was found which is able to predict the maximum adsorption capacities onto the prepared adsorbent for the other cationic dyes.


      PubDate: 2016-06-15T13:31:59Z
       
  • Evaluation of the use of solvent impregnated resins in the analysis of
           salbutamol in human urine followed by capillary electrophoresis
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Irma Pérez-Silva, Ma. Teresa Ramírez-Silva, Carlos A. Galán-Vidal, Giaan A. Álvarez-Romero, José A. Rodríguez, Ma. Elena Páez-Hernández
      In this work, a method for sorption and concentration of salbutamol in urine combined to capillary electrophoresis with UV detection was performed. The procedure is based on the sorption of salbutamol on solvent-impregnated resins that is prepared by an impregnation technique using Aliquat 336 as extractant and XAD-4 resin as the base polymer. Batch studies showed an efficient sorption/desorption results when the salbutamol solution contains NaOH 0.05molL−1 and the eluent is 0.5molL−1 NaCl. Linearity was obtained in the range of 1000–10,000ngmL−1 of salbutamol. The limit of quantification was 999ngmL−1. The solvent-impregnated resin was used for 10cycles without a significant loss of the salbutamol quantification capacity. The method was applied to analyze salbutamol in urine samples at levels useful for international health organizations. Although most reports of solvent impregnated resins are related to the extraction of metal ions and only a few organic compounds, the proposed methodology demonstrate that solvent impregnated resins allows the isolation and concentration of salbutamol from complex samples such as urine. Since no SB is recovered using resin without Aliquat 336, this work shows an advantage of SIR over simple adsorption processes.


      PubDate: 2016-06-15T13:31:59Z
       
  • Preparation of polyaniline-coated polystyrene nanoparticles for the
           sorption of silver ions
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Saurabha Bhattarai, Jong Soo Kim, Yeoung-Sang Yun, Youn-Sik Lee
      Polyaniline-coated polystyrene (PS/PANI) beads with an average diameter of approximately 310nm were prepared from styrene and divinylbenzene via emulsion polymerization and subsequent oxidative polymerization of aniline. The sorption capacity of the polymer beads towards silver ions in aqueous solution increased substantially as the pH increased, up to a pH of 7, owing to more free amine and imine groups. The FE-SEM images and XRD data indicated that silver ions were reduced to form silver nanoparticles on the polymer beads. The kinetics of silver ion uptake by PS/PANI particles in a 160ppm silver nitrate solution could be described by a pseudo-second order model. Even though the sorption isotherm correlated to the Freundlich model much better than the Langmuir model, the Langmuir model-based maximum sorption (320mgg−1) was closer to the experimentally obtained value of 330mgg−1. This study reveals that PS/PANI beads can be readily prepared in large quantities and employed as one of most efficient sorbents of silver ions in the aqueous phase. The high sorption capacity of the polymer nanoparticles was illustrated not to be affected by common alkali and alkaline earth metal ions in a simulated tap water. The PS/PANI nanoparticles were stable enough not to show any significant loss in sorption efficiency even after fourth cycle of adsorption-desorption.
      Graphical abstract image

      PubDate: 2016-06-15T13:31:59Z
       
  • A review of the fabrication of photonic band gap materials based on
           cholesteric liquid crystals
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Rathinam Balamurugan, Jui-Hsiang Liu
      Cholesteric liquid crystals (CLCs) are known to exhibit selective reflection of incident radiation due to their periodic helical structure, which makes them promising candidates for a myriad of different photonic applications. At normal incidence, CLCs reflect circularly polarized incident light of the same handedness as the cholesteric helix and of wavelength λ between noP and neP, where no and ne are the ordinary and extraordinary refractive indices, respectively, of the locally uniaxial structure, and P is the pitch of the helix. Thus, the reflection bandwidth Δλ is given by Δλ=ΔnP, where the birefringence Δn=ne −no. Within the bandwidth, right-circularly polarized light is reflected by a right-handed helix, whereas left-circularly polarized light is transmitted. Outside the bandwidth, both polarization states are transmitted. Therefore, Δλ depends on Δn. Moreover, Δn is typically limited to 0.3–0.4 for colorless organic compounds, and Δλ is often <100nm in the visible spectrum. Although a narrow reflection band is desirable for applications such as optical filters and thermal imaging, it also becomes a drawback in their applications, such as reflective displays, broadband circular polarizers and switchable mirrors. The purpose of this review is to take a closer look into how to broaden the reflection band in CLCs to overcome the above limitations for a wide variety of applications. This review covers the methodology that was used until recently, when the fabrication of photonic band gap (PBG) materials arose, based on CLCs. The mechanisms for broadening the reflection band have been reviewed.


      PubDate: 2016-06-15T13:31:59Z
       
  • Architecture of Ba/alginate/dextran stabilized Au, Fe3O4, TiO2 &
           silica nanoparticles gels and their applications for reduction of
           4-nitrophenol and glucose sensing
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Molly Thomas, Gowhar Ahmad Naikoo, Mehraj Ud Din Sheikh, Mustri Bano, Farid Khan
      An innovative method is presented to produce anisotropically ordered capillaries and small pores by dissipative convective process followed by simple freezing in liquid nitrogen of Ba/alginate/dextran hydrogels with and without nanoparticles. Magnetite, gold, silica or titanium dioxide nanoparticles were encapsulated safely into the gels with protecting their stability and microstructures. Mechanical strength and rheological studies of the gels were also investigated. Ba/alginate/dextran/Au composite gel has shown excellent catalytic activity for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in presence of NaBH4 with a rate constant of 6.85×10−3 min−1. Ba/Alg/Dex/Au-GCE exhibits non-enzymatic electrocatalytic oxidation of glucose with linear range from 1mM to 10mM (r=0.998) and the detection limit to 63μM at a signal-to-noise ratio of 3.


      PubDate: 2016-06-15T13:31:59Z
       
  • Multi-stimuli-responsive semi-IPN cryogels with native and anionic potato
           starch entrapped in poly(N,N-dimethylaminoethyl methacrylate) matrix and
           their potential in drug delivery
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Ecaterina Stela Dragan, Diana Felicia Apopei Loghin, Ana-Irina Cocarta, Mirela Doroftei
      This study was focused on the preparation of novel multi-stimuli-responsive semi-interpenetrating polymer networks (semi-IPN) hydrogels by cross-linking polymerization of N,N-dimethylaminoethyl methacrylate (DMAEM) in the presence of potato starch (PS) or anionically modified PS by using ice-templating strategy (−18°C). Cryogelation was used for this aim because it allowed decreasing the monomer concentration to 10wt.% and a very fast response at swelling of the composite gels. Furthermore, the anionically modified PS allowed the decrease of the volume phase transition temperature (VPTT) of the composite cryogels by its electrostatic interactions with the matrix. After the characterization of the composite structure by Fourier transform infrared spectroscopy and of the macroporous morphology by scanning electron microscopy analysis, the effect of the entrapped polysaccharide on the swelling properties of the composite cryogels, and their response at three stimuli (pH, temperature and ion nature and concentration) were deeply investigated. The VPTT of the composite cryogels was situated in the range 36–39°C, the particular value depending on the DMAEM concentration and on the nature and content of polysaccharide. After that, diclofenac sodium (DS), taken as a model acidic drug, was easily loaded into the composite cryogels by the solvent sorption–evaporation strategy due to the interconnected pores of these materials. The controlled delivery of DS from the novel semi-IPN composite cryogels was then optimized by the investigation of the effects of pH, temperature, and cycling changes of the release temperature. It was found that these composite cryogels are promising systems for the sustained delivery of DS in the simulated intestinal fluid, but not in the simulated gastric fluid, and this recommends them as vehicles of drugs in colon. Finally, the release mechanism of DS from the composite cryogels was discussed based on two kinetic models.


      PubDate: 2016-06-15T13:31:59Z
       
  • Conducting semi-interpenetrating polymeric composites via the preparation
           of poly(aniline), poly(thiophene), and poly(pyrrole) polymers within
           superporous poly(acrylic acid) cryogels
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Nurettin Sahiner, Sahin Demirci
      In this study, a novel and special form of hydrogel known as cryogel with super and interconnected pore structures was synthesized as p(acrylic acid) (p(AAc)) cryogel by a cryopolymerization technique. Then, the superporous p(AAc) cryogels were used as template for the synthesis of conductive polymers such as poly(aniline) (p(An)), poly(thiophene) (p(Th)), and poly(pyrrole) (p(Py)). To the best of the authors' knowledge, this is the first study of its kind to report the synthesis of conductive polymers, p(An), p(Th), and p(Py), within the superporous network of cryogel. The synthesized p(AAc)/p(An), p(AAc)/p(Th), and p(AAc)/p(Py) conducting semi-interpenetrating polymeric network (semi-IPN) cryogel composites were characterized by using Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), and conductivity measurements. The conductivities of p(AAc)/p(An), p(AAc)/p(Th), and p(AAc)/p(Py) toward semi-IPN cryogels were measured as 2.2×10−4 ±1×10−5, 3.2×10−4 ±0.9×10−5, and 3.2×10−3 ±5×10−4 Scm−1, whereas the conductivity of bare p(AAc) cryogels was calculated to be about 3.2×10−9 ±2.1×10−10 Scm−1.


      PubDate: 2016-06-15T13:31:59Z
       
  • Utility of PCDTBT polymer for the superior sensing parameters of
           electrical response based relative humidity sensor
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): Qayyum Zafar, Khaulah Sulaiman
      In the present study, organic polymer PCDTBT has been deposited on pair of planar aluminium (Al) electrodes to construct an integrated capacitive and impedance type humidity sensor (Al/PCDTBT/Al). The solution processable organic polymer has been deposited through a facile spin coating technique. The structural characterization and surface morphology study of active layer has been performed by XRD and AFM. The humidity sensing characteristics of the sensor have been investigated by exposing the organic active layer to various wide range relative humidity (%RH) levels (15–98%RH) at room temperature. The proposed sensor exhibits significantly higher sensitivity ~39.73pF/%RH and 821.81kΩ/%RH when operated in capacitive and impedance mode, respectively. In addition, the capacitive sensor has desirable reproducibility, narrow hysteresis (~5%), fast response (8s) and reset (14s) time. Significantly improved sensing parameters suggest that the proposed sensor may be implemented meritoriously for continuous humidity assessment in environment.


      PubDate: 2016-06-15T13:31:59Z
       
  • Metal nanoparticles designed PET: Preparation, characterization and
           biological response
    • Abstract: Publication date: August 2016
      Source:Reactive and Functional Polymers, Volume 105
      Author(s): A. Reznickova, J. Siegel, N. Slavikova, Z. Kolska, M. Staszek, V. Svorcik
      In this manuscript, Ar plasma treated polyethyeterephthalate grafted with biphenyl-4,4′-dithiol interlayer and subsequently with green synthesized Pt and Pd nanoparticles is studied, focusing on the cytocompatibility of those composites. Changes in surface properties of the plasma treated and nanoparticle-grafted PET surface were studied in relation to in vitro adhesion and proliferation of mouse fibroblasts (L929) and human osteoblast (U-2 OS). Prepared samples were studied by several experimental techniques: goniometry, angle resolved X-ray photoelectron spectroscopy (ARXPS), ultraviolet–visible spectroscopy (UV–vis), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDS) and electrokinetic analysis. Ageing of the modified PET was accompanied by an increase of the contact angle which was due to a reorientation of the molecular polar segments produced during the plasma treatment. FTIR, UV–vis, ARXPS measurements and zeta potential indicate that the thiols were chemically bonded to the surface of the plasma treated polymers and that the thiols mediate subsequent grafting of Pt and Pd nanoparticles. Generally, EDS revealed that Pt nanoparticles are homogeneously distributed over the whole surface and Pd nanoparticles tend to aggregate slightly. In case of L929 cells, the chemical anchoring of Pt nanoparticles to PET surface significantly enhanced cell adhesion and proliferation compared to pristine PET.
      Graphical abstract image

      PubDate: 2016-06-15T13:31:59Z
       
  • Comparison between two different click strategies to synthesize
           fluorescent nanogels for therapeutic applications
    • Abstract: Publication date: Available online 10 May 2016
      Source:Reactive and Functional Polymers
      Author(s): Emanuele Mauri, Irene Moroni, Luca Magagnin, Maurizio Masi, Alessandro Sacchetti, Filippo Rossi
      The development of nanogels as nanoscale multifunctional polymer-based matrices for controlled drug and gene delivery purposes has been the subject of intense research during the last decades. Their use in biomedical field is related to the effect of their size on the interactions with living cells: only within a defined range nanoparticles could be subjected to active or passive cellular uptake. In this work we propose two methods to synthetize Rhodamine modified nanogels in order to produce nanostructures that could be traced during the cellular interactions and internalization and suitable as carrier for drugs or genes. We compared the obtained sizes and charges of both nanogels, underlining which one could be more useful for biological and therapeutic applications referring to the morphological and physico-chemical properties requested in accordance with medical needs. We also tested their cytocompatibility and their characteristic behavior as drug delivery vehicles.
      Graphical abstract image

      PubDate: 2016-05-10T18:54:30Z
       
  • Fabrication of self-cross-linking fluorinated polyacrylate latex particles
           with core-shell structure and film properties
    • Abstract: Publication date: Available online 26 April 2016
      Source:Reactive and Functional Polymers
      Author(s): Ting Lü, Dongming Qi, Dong Zhang, Qian Liu, Hongting Zhao
      A series of self-cross-linking fluorinated polyacrylate latex particles with core-shell structure were successfully prepared by one-step miniemulsion polymerization of methyl methacrylate (MMA), butyl acrylate (BA), dodecafluoroheptyl methacrylate (DFMA), and γ-methacryloxypropyl triisopropoxidesilane (MPS). The core-shell structure of the latex particles was confirmed and the latex films were characterized. Results showed that the latex films not only showed enhanced thermostability but also exhibited good hydrophobic property with the incorporation of a small amount of MPS (below 5wt% of monomers). This core-shell fluorine/silicone-containing polyacrylate latex could potentially be used for developing advanced multifunctional protective coatings such as antiwetting, anti-icing, antifogging, and anticorrosion.


      PubDate: 2016-04-29T18:48:56Z
       
  • Ring expansion-controlled radical polymerization: Synthesis of cyclic
           polymers and ring component quantification based on SEC–MALS analysis
    • Abstract: Publication date: Available online 20 April 2016
      Source:Reactive and Functional Polymers
      Author(s): Atsushi Narumi, Shuhei Hasegawa, Ryo Yanagisawa, Miho Tomiyama, Masatsugu Yamada, Wolfgang H. Binder, Moriya Kikuchi, Seigou Kawaguchi
      We report a ring expansion vinyl polymerization producing cyclic polymers using a tetra(oxyethylene) (TOE)-tethered cyclic initiator for the nitroxide-mediated controlled radical polymerization (NMP). Styrene (St) was polymerized with the cyclic NMP initiator 1 in the bulk to produce polymer 2. Structural analyses of 2 were performed by a size exclusion chromatograph equipped with a multiangle laser light scattering (SEC–MALS) detector, focusing on the relationships between the z-averaged root-mean-square radii of gyration (〈S 2〉z 1/2) versus the molecular weights. The results proved that 2 would consist of ring components as a result of the ring expansion polymerizations and radical ring crossover reactions together with ring-opened linear components, in which the amount of ring components increased with the increasing molecular weights. The data also enabled the quantification that approximately 13–40wt% of the final polymer 2 could be identified as the ring species in the M w range of 1×105–5×105 gmol−1.


      PubDate: 2016-04-24T18:47:28Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.144.15.10
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2016